STEEL FOR STEEL PIPE - SUMITOMO METAL IND

Title:

STEEL FOR STEEL PIPE

Document Type and Number:

WIPO Patent Application WO/2006/009142

Kind Code:

A1

Abstract:

A steel for a steel pipe which has a chemical composition that C: 0.2 to 0.7 %, Si: 0.01 to 0.8 %, Mn: 0.1 to 1.5 %, S: 0.005 % or less, P: 0.03 % or less, Al: 0.0005 to 0.1 %, Ti: 0.005 to 0.05%, Ca: 0.0004 to 0.005 %, N: 0.007 % or less, Cr: 0.1 to 1.5 %, Mo: 0.2 to 1.0 %, Nb: 0 to 0.1 %, Zr: 0 to 0.1 %, V: 0 to 0.5 %, B: 0 to 0.005 %, and the balance: Fe and impurities, and contains non-metal inclusions containing Ca, Al, Ti, N, O (oxygen) and S, wherein the inclusions have a (Ca %)/(Al %) of 0.55 to 1.72, and a (Ca %)/(Ti %) of 0.7 to 19. The above steel for a steel pipe can be used as a raw material of a steel pipe for an oil well pipe, such as a casing and a tubing of a greatly deep oil or natural gas well and an oil or natural gas well located in a severe corrosion circumstance and a drill pipe and a drill collar for use in excavation.

Inventors:

NUMATA MITSUHIRO (JP)
OMURA TOMOHIKO (JP)
HIGUCHI YOSHIHIKO (JP)

Application Number:

PCT/JP2005/013249

Publication Date:

January 26, 2006

Filing Date:

July 19, 2005

Export Citation:

Click for automatic bibliography generation Help

Assignee:

SUMITOMO METAL IND (JP)
NUMATA MITSUHIRO (JP)
OMURA TOMOHIKO (JP)
HIGUCHI YOSHIHIKO (JP)

International Classes:

C22C30/00; C21C7/04; C22C38/28; C22C38/32

Foreign References:

JP2004002978A	2004-01-08
JP2003129179A	2003-05-08
JP2002060893A	2002-02-28

Other References: